摘要 |
A detecting device includes: an actuator with its end placed in a conveying path of a moving object such as a sheet etc., pivotally supported by a rotary shaft so that it can sway as the moving object passes by; a slit arm integrally formed with the actuator and having a slit therein and an optical sensor disposed below the actuator. In this arrangement, the slit arm having a slit therein is placed in the path of the optical sensor. An urging portion for returning the actuator to the standby position is provided for the slit arm. The abutment surface P of the urging portion abutting the unit base of the optical sensor is formed inclined. A component force E causing the actuator to bounce, which is proportional to a repulsive force D normal to the abutment surface P when the abutment surface abuts the unit base abutment surface P, is smaller than the repulsive force D. Therefore, the distance of the bouncing of the actuator becomes smaller, thus preventing chattering. <IMAGE> |